SORL1 and Alzheimer disease: Second, genome-wide association studies (GWASs) identified several susceptibility loci associated with AD (APOE, BIN1, PICALM, CD33, ABCA7, CLU, MS4A6A, EPHA1, CR1, CD2AP, SORL1, CASS4) and regulating APP-Aβ levels [5–12].